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Show KEEPING SHIPS FROM ROLLING I The principle of the gyroscope, while -simple and generally understood, under-stood, can' be applied at ' times to: produce some very puzzling results, and in order that the method of Its application to ship's rolling may bo more clearly understood, It may perhaps per-haps be as well to review this principle prin-ciple In the simplest possible way. , Suppose we have a vertical spindle and on it mount a wheel in what Is called tho natural or horl-zontal horl-zontal plane, the spjndle bolng so arranged that u can be tilted in any direction. To consider the matter concretely, let us suppose that the wheel Is spinning at a high rate of speed and that we so tilt the spindle, that its top moves toward the north. What ' happens? As soon as tho top of the spindle Is given this angular an-gular motion, the .spinning will develop de-velop a couple which- tends to tilt the spindle either to the eastward or westward, according to tho direction di-rection In which the wheel Is spinning. spin-ning. The movement of tho gyroscope gyro-scope Is thus seen to take place In the plane at right angles to that of the impressed force. This movo-ment movo-ment normal to the impressed force is called "precession," . Many years ago that able naval architect and Investigator, Sir J. I. Thornycroft, evolved a schome for preventlng rolling by means of shifting shift-ing a heavy weight, the controlling . t , mechanism being by means of ft gyroscope. j? Later on,ta German, engineer, 'Doo J- tor Schllck, developed What is called j" tho "passive" type of gyroscope. which utilized the periodic motions p of a ship after they had been de veloped by tho actions of the sea for damping pr reducing the roll- f lng. r Mr. Sperry attackea the problepi from a totally different and more f aggrosslvo point, and proposed to install an "active" type of gyroscope j. equipment which did not wait for '. the ship to roll before it began Its t " work, but which prevented Instant- " r, ly, at 4 its inception, any rolling A , movement or the Vessel. j There is a very Important point to be observed here. Each ten dency to roll Is quelled on the In- - slant, and simultaneously with Its ,' , development. Is completely neutral- j ized before It has time to move th a Hip'. There is thus practically no ; angular motion. ' If the reader will remember that t without angular motion a couplo i exerted by a gyroscope becomes ? zero, then ho will readily tinder- h L stand that It requires practically j zero work to resist tho couple In J other words, when a ship Is hel-l practically free "from, rolling. It re- quires very little power to main- ; tain It in this condition, nnd this ( 5 has been found to be actually tn case in practice, us has been thor x oughly demonstrated. At first sight j this may seem revolutionary, but K r jj Is nevertheless true, and it Is this p feature of the development the : should work a revolution in oxr f methods of stabilizing ships. ?; . j i f |